
{$mode objfpc}
unit libmpv;
interface
uses
  ctypes;

const
  {$IFDEF LINUX}
     External_library='libmpv.so.1';
  {$ENDIF LINUX}
  {$IFDEF WINDOWS}
     External_library='libmpv.dll';
  {$ENDIF LINUX}
  {$IFDEF DARWIN}
     External_library = 'libmpv.dylib';
  {$ENDIF DARWIN}


  { Pointers to basic pascal types, inserted by h2pas conversion program.}
  Type
    PLongint  = ^Longint;
    PSmallInt = ^SmallInt;
    PByte     = ^Byte;
    PWord     = ^Word;
    PDWord    = ^DWord;
    PDouble   = ^Double;

    Pmpv_handle  = ^mpv_handle;
    mpv_handle = Thandle;

  { Permission to use, copy, modify, and/or distribute this software for any
   * purpose with or without fee is hereby granted, provided that the above
   * copyright notice and this permission notice appear in all copies.
   *
   * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
   * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
   * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
   * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
   * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
   * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
   * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
    }
  {
   * Note: the client API is licensed under ISC (see above) to ease
   * interoperability with other licenses. But keep in mind that the
   * mpv core is still mostly GPLv2+. It's up to lawyers to decide
   * whether applications using this API are affected by the GPL.
   * One argument against this is that proprietary applications
   * using mplayer in slave mode is apparently tolerated, and this
   * API is basically equivalent to slave mode.
    }
 {*
   * Mechanisms provided by this API
   * -------------------------------
   *
   * This API provides general control over mpv playback. It does not give you
   * direct access to individual components of the player, only the whole thing.
   * It's somewhat equivalent to MPlayer's slave mode. You can send commands,
   * retrieve or set playback status or settings with properties, and receive
   * events.
   *
   * The API can be used in two ways:
   * 1) Internally in mpv, to provide additional features to the command line
   *    player. Lua scripting uses this. (Currently there is no plugin API to
   *    get a client API handle in external user code. It has to be a fixed
   *    part of the player at compilation time.)
   * 2) Using mpv as a library with mpv_create(). This basically allows embedding
   *    mpv in other applications.
   *
   * Event loop
   * ----------
   *
   * In general, the API user should run an event loop in order to receive events.
   * This even loop should call mpv_wait_event(), which will return once a new
   * mpv client API is available. It should also be possible to integrate client
   * API usage in other event loops (e.g. GUI toolkits) with the
   * mpv_set_wakeup_callback() function, and then polling for events by calling
   * mpv_wait_event() with a 0 timeout.
   *
   * Note that the event loop is detached from the actual player. Not calling
   * mpv_wait_event() will not stop playback. It will eventually congest the
   * event queue of your API handle, though.
   *
   * Synchronous vs. asynchronous calls
   * ----------------------------------
   *
   * The API allows both synchronous and asynchronous calls. Synchronous calls
   * have to wait until the playback core is ready, which currently can take
   * an unbounded time (e.g. if network is slow or unresponsive). Asynchronous
   * calls just queue operations as requests, and return the result of the
   * operation as events.
   *
   * Asynchronous calls
   * ------------------
   *
   * The client API includes asynchronous functions. These allow you to send
   * requests instantly, and get replies as events at a later point. The
   * requests are made with functions carrying the _async suffix, and replies
   * are returned by mpv_wait_event() (interleaved with the normal event stream).
   *
   * A 64 bit userdata value is used to allow the user to associate requests
   * with replies. The value is passed as reply_userdata parameter to the request
   * function. The reply to the request will have the reply
   * mpv_event->reply_userdata field set to the same value as the
   * reply_userdata parameter of the corresponding request.
   *
   * This userdata value is arbitrary and is never interpreted by the API. Note
   * that the userdata value 0 is also allowed, but then the client must be
   * careful not accidentally interpret the mpv_event->reply_userdata if an
   * event is not a reply. (For non-replies, this field is set to 0.)
   *
   * Currently, asynchronous calls are always strictly ordered (even with
   * synchronous calls) for each client, although that may change in the future.
   *
   * Multithreading
   * --------------
   *
   * The client API is generally fully thread-safe, unless otherwise noted.
   * Currently, there is no real advantage in using more than 1 thread to access
   * the client API, since everything is serialized through a single lock in the
   * playback core.
   *
   * Basic environment requirements
   * ------------------------------
   *
   * This documents basic requirements on the C environment. This is especially
   * important if mpv is used as library with mpv_create().
   *
   * - The LC_NUMERIC locale category must be set to "C". If your program calls
   *   setlocale(), be sure not to use LC_ALL, or if you do, reset LC_NUMERIC
   *   to its sane default: setlocale(LC_NUMERIC, "C").
   * - If a X11 based VO is used, mpv will set the xlib error handler. This error
   *   handler is process-wide, and there's no proper way to share it with other
   *   xlib users within the same process. This might confuse GUI toolkits.
   * - mpv uses some other libraries that are not library-safe, such as Fribidi
   *   (used through libass), LittleCMS, ALSA, FFmpeg, and possibly more.
   * - The FPU precision must be set at least to double precision.
   * - On Windows, mpv will call timeBeginPeriod(1).
   * - On memory exhaustion, mpv will kill the process.
   *
   * Embedding the video window
   * --------------------------
   *
   * Currently you have to get the raw window handle, and set it as "wid" option.
   * This works on X11 and win32 only. In addition, it works with a few VOs only,
   * and VOs which do not support this will just create a freestanding window.
   *
   * Both on X11 and win32, the player will fill the window referenced by the
   * "wid" option fully and letterbox the video (i.e. add black bars if the
   * aspect ratio of the window and the video mismatch).
   *
   * On OSX, embedding is not yet possible, because Cocoa makes this non-trivial.
    }
  {*
   * The version is incremented on each API change. The 16 lower bits form the
   * minor version number, and the 16 higher bits the major version number. If
   * the API becomes incompatible to previous versions, the major version
   * number is incremented. This affects only C part, and not properties and
   * options.
    }

  const
    _MPV_CLIENT_API_VERSION = $00010000;
  {*
   * Return the MPV_CLIENT_API_VERSION the mpv source has been compiled with.
    }

  var
    mpv_client_api_version : function:dword;cdecl;
  {*
   * Client context used by the client API. Every client has its own private
   * handle.
    }

  type
  {*
   * List of error codes than can be returned by API functions. 0 and positive
   * return values always mean success, negative values are always errors.
    }
  {*
       * No error happened (used to signal successful operation).
       * Keep in mind that many API functions returning error codes can also
       * return positive values, which also indicate success. API users can
       * hardcode the fact that ">= 0" means success.
        }
  {*
       * The event ringbuffer is full. This means the client is choked, and can't
       * receive any events. This can happen when too many asynchronous requests
       * have been made, but not answered. Probably never happens in practice,
       * unless the mpv core is frozen for some reason, and the client keeps
       * making asynchronous requests. (Bugs in the client API implementation
       * could also trigger this, e.g. if events become "lost".)
        }
  {*
       * Memory allocation failed.
        }
  {*
       * The mpv core wasn't configured and initialized yet. See the notes in
       * mpv_create().
        }
  {*
       * Generic catch-all error if a parameter is set to an invalid or
       * unsupported value. This is used if there is no better error code.
        }
  {*
       * Trying to set an option that doesn't exist.
        }
  {*
       * Trying to set an option using an unsupported MPV_FORMAT.
        }
  {*
       * Setting the option failed. Typically this happens if the provided option
       * value could not be parsed.
        }
  {*
       * The accessed property doesn't exist.
        }
  {*
       * Trying to set or get a property using an unsupported MPV_FORMAT.
        }
  {*
       * The property exists, but is not available. This usually happens when the
       * associated subsystem is not active, e.g. querying audio parameters while
       * audio is disabled.
        }
  {*
       * Error setting or getting a property.
        }
  {*
       * General error when running a command with mpv_command and similar.
        }

    mpv_error =  Longint;
    Const
      MPV_ERROR_SUCCESS = 0;
      MPV_ERROR_EVENT_QUEUE_FULL = -(1);
      MPV_ERROR_NOMEM = -(2);
      MPV_ERROR_UNINITIALIZED = -(3);
      MPV_ERROR_INVALID_PARAMETER = -(4);
      MPV_ERROR_OPTION_NOT_FOUND = -(5);
      MPV_ERROR_OPTION_FORMAT = -(6);
      MPV_ERROR_OPTION_ERROR = -(7);
      MPV_ERROR_PROPERTY_NOT_FOUND = -(8);
      MPV_ERROR_PROPERTY_FORMAT = -(9);
      MPV_ERROR_PROPERTY_UNAVAILABLE = -(10);
      MPV_ERROR_PROPERTY_ERROR = -(11);

  {*
   * Return a string describing the error. For unknown errors, the string
   * "unknown error" is returned.
   *
   * @param error error number, see enum mpv_error
   * @return A static string describing the error. The string is completely
   *         static, i.e. doesn't need to be deallocated, and is valid forever.
    }


  var
    mpv_error_string : function(error:longint):Pchar;cdecl;
  {*
   * General function to deallocate memory returned by some of the API functions.
   * Call this only if it's explicitly documented as allowed. Calling this on
   * mpv memory not owned by the caller will lead to undefined behavior.
   *
   * @param data A valid pointer returned by the API, or NULL.
    }
    mpv_free : procedure(var data:pointer);cdecl;
  {*
   * Return the name of this client handle. Every client has its own unique
   * name, which is mostly used for user interface purposes.
   *
   * @return The client name. The string is read-only and is valid until the
   *         mpv_handle is destroyed.
    }

    mpv_client_name : function(var ctx:mpv_handle):Pchar;cdecl;
  {*
   * Create a new mpv instance and an associated client API handle to control
   * the mpv instance. This instance is in a pre-initialized state,
   * and needs to be initialized to be actually used with most other API
   * functions.
   *
   * Most API functions will return MPV_ERROR_UNINITIALIZED in the uninitialized
   * state. You can call mpv_set_option() (or mpv_set_option_string() and other
   * variants) to set initial options. After this, call mpv_initialize() to start
   * the player, and then use e.g. mpv_command() to start playback of a file.
   *
   * The point of separating handle creation and actual initialization is that
   * you can configure things which can't be changed during runtime.
   *
   * Unlike the command line player, this will have initial settings suitable
   * for embedding in applications. The following settings are different:
   * - stdin/stdout/stderr and the terminal will never be accessed. This is
   *   equivalent to setting the --no-terminal option.
   *   (Technically, this also suppresses C signal handling.)
   * - No config files will be loaded. This is roughly equivalent to using
   *   --no-config (but actually the code path for loading config files is
   *   disabled).
   * - Idle mode is enabled, which means the playback core will enter idle mode
   *   if there are no more files to play on the internal playlist, instead of
   *   exiting. This is equivalent to the --idle option.
   * - Disable parts of input handling.
   *
   * All this assumes that API users want a mpv instance that is strictly
   * isolated from the command line player's configuration, user settings, and
   * so on. You can re-enable disabled features by setting the appropriate
   * options.
   *
   * The mpv command line parser is not available through this API, but you can
   * set individual options with mpv_set_option(). Files for playback must be
   * loaded with mpv_command() or others.
   *
   * Note that you should avoid doing concurrent accesses on the uninitialized
   * client handle. (Whether concurrent access is definitely allowed or not has
   * yet to be decided.)
   *
   * @return a new mpv client API handle
    }
    mpv_create : function:Pmpv_handle;cdecl;
  {*
   * Initialize an uninitialized mpv instance. If the mpv instance is already
   * running, an error is retuned.
   *
   * This function needs to be called to make full use of the client API if the
   * client API handle was created with mpv_create().
   *
   * @return error code
    }
    mpv_initialize : function(var ctx:mpv_handle):longint;cdecl;
  {*
   * Disconnect and destroy the mpv_handle. ctx will be deallocated with this
   * API call. This leaves the player running. If you want to be sure that the
   * player is terminated, send a "quit" command, and wait until the
   * MPV_EVENT_SHUTDOWN event is received, or use mpv_terminate_destroy().
    }
    mpv_detach_destroy : procedure(var ctx:mpv_handle);cdecl;
  {*
   * Similar to mpv_detach_destroy(), but brings the player and all clients down
   * as well, and waits until all of them are destroyed. This function blocks. The
   * advantage over mpv_detach_destroy() is that while mpv_detach_destroy() merely
   * detaches the client handle from the player, this function quits the player,
   * waits until all other clients are destroyed (i.e. all mpv_handles are
   * detached), and also waits for the final termination of the player.
   *
   * Since mpv_detach_destroy() is called somewhere on the way, it's not safe to
   * call other functions concurrently on the same context.
   *
   * If this is called on a mpv_handle that was not created with mpv_create(),
   * this function will merely send a quit command and then call
   * mpv_detach_destroy(), without waiting for the actual shutdown.
    }
    mpv_terminate_destroy : procedure(var ctx:mpv_handle);cdecl;
  {*
   * Load a config file. This loads and parses the file, and sets every entry in
   * the config file's default section as if mpv_set_option_string() is called.
   *
   * The filename should be an absolute path. If it isn't, the actual path used
   * is unspecified. (Note: an absolute path starts with '/' on UNIX.) If the
   * file wasn't found, MPV_ERROR_INVALID_PARAMETER is returned.
   *
   * If a fatal error happens when parsing a config file, MPV_ERROR_OPTION_ERROR
   * is returned. Errors when setting options as well as other types or errors
   * are ignored (even if options do not exist). You can still try to capture
   * the resulting error messages with mpv_request_log_messages(). Note that it's
   * possible that some options were successfully set even if any of these errors
   * happen.
   *
   * The same restrictions as with mpv_set_option() apply: some options can't
   * be set outside of idle or uninitialized state, and many options don't
   * take effect immediately.
   *
   * @param filename absolute path to the config file on the local filesystem
   * @return error code
    }

    mpv_load_config_file : function(var ctx:mpv_handle; filename:Pchar):longint;cdecl;
  {*
   * Stop the playback thread. Normally, the client API stops the playback thread
   * automatically in order to process requests. However, the playback thread is
   * restarted again after the request was processed. Then the playback thread
   * will continue to display the next video frame, during which it will not
   * reply to any requests. (This takes up to 50ms.)
   *
   * (Internally, it first renders the video and other things, and then blocks
   * until it can be displayed - and it won't react to anything else in that
   * time. The main reason for that is that the VO is in a "in between" state,
   * in which it can't process normal requests - for example, OSD redrawing or
   * screenshots would be broken.)
   *
   * This is usually a problem: only 1 request per video frame will be executed,
   * which will make the client API to appear extremely slow.
   *
   * Suspending the playback thread allows you to prevent the playback thread from
   * running, so that you can make multiple accesses without being blocked.
   *
   * Suspension is reentrant and recursive for convenience. Any thread can call
   * the suspend function multiple times, and the playback thread will remain
   * suspended until the last thread resumes it. Note that during suspension,
   * clients still have concurrent access to the core, which is serialized through
   * a single mutex.
   *
   * Call mpv_resume() to resume the playback thread. You must call mpv_resume()
   * for each mpv_suspend() call. Calling mpv_resume() more often than
   * mpv_suspend() is not allowed.
   *
   * Calling this on an uninitialized player (see mpv_create()) will deadlock.
   *
   * Note: the need for this call might go away at some point.
    }
    mpv_suspend : procedure(var ctx:mpv_handle);cdecl;
  {*
   * See mpv_suspend().
    }
    mpv_resume : procedure(var ctx:mpv_handle);cdecl;
  {*
   * Return the internal time in microseconds. This has an arbitrary start offset,
   * but will never wrap or go backwards.
   *
   * Note that this is always the real time, and doesn't necessarily have to do
   * with playback time. For example, playback could go faster or slower due to
   * playback speed, or due to playback being paused. Use the "time-pos" property
   * instead to get the playback status.
    }
    mpv_get_time_us : function(var ctx:mpv_handle):int64;cdecl;
  {*
   * Data format for options and properties. The API functions to get/set
   * properties and options support multiple formats, and this enum describes
   * them.
    }
  {*
       * Invalid. Sometimes used for empty values.
        }
  {*
       * The basic type is char*. It returns the raw property string, like
       * using $=property in input.conf (see input.rst).
       *
       * NULL isn't an allowed value.
       *
       * Warning: although the encoding is usually UTF-8, this is not always the
       *          case. File tags often store strings in some legacy codepage,
       *          and even filenames don't necessarily have to be in UTF-8 (at
       *          least on Linux). If you pass the strings to code that requires
       *          valid UTF-8, you have to sanitize it in some way.
       *
       * Example for reading:
       *
       *     char *result = NULL;
       *     if (mpv_get_property(ctx, "property", MPV_FORMAT_STRING, &result) < 0)
       *         goto error;
       *     printf("%s\n", result);
       *     mpv_free(result);
       *
       * Or just use mpv_get_property_string().
       *
       * Example for writing:
       *
       *     char *value = "the new value";
       *     // yep, you pass the address to the variable
       *     // (needed for symmetry with other types and mpv_get_property)
       *     mpv_set_property(ctx, "property", MPV_FORMAT_STRING, &value);
       *
       * Or just use mpv_set_property_string().
       *
        }
  {*
       * The basic type is char*. It returns the OSD property string, like
       * using $property in input.conf (see input.rst). In many cases, this
       * is the same as the raw string, but in other cases it's formatted for
       * display on OSD. It's intended to be human readable. Do not attempt to
       * parse these strings.
       *
       * Only valid when doing read access. The rest works like MPV_FORMAT_STRING.
        }
  {*
       * The basic type is int. The only allowed values are 0 ("no")
       * and 1 ("yes").
       *
       * Example for reading:
       *
       *     int result;
       *     if (mpv_get_property(ctx, "property", MPV_FORMAT_FLAG, &result) < 0)
       *         goto error;
       *     printf("%s\n", result ? "true" : "false");
       *
       * Example for writing:
       *
       *     int flag = 1;
       *     mpv_set_property(ctx, "property", MPV_FORMAT_STRING, &flag);
        }
  {*
       * The basic type is int64_t.
        }
  {*
       * The basic type is double.
        }
  {*
       * The type is mpv_node.
       *
       * For reading, you usually would pass a pointer to a stack-allocated
       * mpv_node value to mpv, and when you're done you call
       * mpv_free_node_contents(&node).
       * You're expected not to write to the data - if you have to, copy it
       * first (which you have to do manually).
       *
       * For writing, you construct your own mpv_node, and pass a pointer to the
       * API. The API will never write to your data (and copy it if needed), so
       * you're free to use any form of allocation or memory management you like.
       *
       * Warning: when reading, always check the mpv_node.format member. For
       *          example, properties might change their type in future versions
       *          of mpv, or sometimes even during runtime.
       *
       * Example for reading:
       *
       *     mpv_node result;
       *     if (mpv_get_property(ctx, "property", MPV_FORMAT_NODE, &result) < 0)
       *         goto error;
       *     printf("format=%d\n", (int)result.format);
       *     mpv_free_node_contents(&result).
       *
       * Example for writing:
       *
       *     mpv_node value;
       *     value.format = MPV_FORMAT_STRING;
       *     value.u.string = "hello";
       *     mpv_set_property(ctx, "property", MPV_FORMAT_NODE, &value);
        }
  {*
       * Used with mpv_node only. Can usually not be used directly.
        }
  {*
       * See MPV_FORMAT_NODE_ARRAY.
        }

  type
    Pmpv_format = ^mpv_format;
    mpv_format =  int64;
    Const
      MPV_FORMAT_NONE = 0;
      MPV_FORMAT_STRING = 1;
      MPV_FORMAT_OSD_STRING = 2;
      MPV_FORMAT_FLAG = 3;
      MPV_FORMAT_INT64 = 4;
      MPV_FORMAT_DOUBLE = 5;
      MPV_FORMAT_NODE = 6;
      MPV_FORMAT_NODE_ARRAY = 7;
      MPV_FORMAT_NODE_MAP = 8;

  {*
   * Generic data storage.
   *
   * If mpv writes this struct (e.g. via mpv_get_property()), you must not change
   * the data. In some cases (mpv_get_property()), you have to free it with
   * mpv_free_node_contents(). If you fill this struct yourself, you're also
   * responsible for freeing it, and you must not call mpv_free_node_contents().
    }
  {* valid if format==MPV_FORMAT_STRING  }
  {* valid if format==MPV_FORMAT_FLAG    }
(* error
        int64_t int64;  /** valid if format==MPV_FORMAT_INT64  */
 in declarator_list *)
  {* valid if format==MPV_FORMAT_INT64   }
  {* valid if format==MPV_FORMAT_DOUBLE  }
  {*
           * valid if format==MPV_FORMAT_NODE_ARRAY
           *    or if format==MPV_FORMAT_NODE_MAP
            }
  {*
       * Type of the data stored in this struct. This value rules what members in
       * the given union can be accessed. The following formats are currently
       * defined to be allowed in mpv_node:
       *
       *  MPV_FORMAT_STRING       (u.string)
       *  MPV_FORMAT_FLAG         (u.flag)
       *  MPV_FORMAT_INT64        (u.int64)
       *  MPV_FORMAT_DOUBLE       (u.double_)
       *  MPV_FORMAT_NODE_ARRAY   (u.list)
       *  MPV_FORMAT_NODE_MAP     (u.list)
       *  MPV_FORMAT_NONE         (no member)
       *
       * If you encounter a value you don't know, you must not make any
       * assumptions about the contents of union u.
        }

  type
    Pmpv_node = ^mpv_node;
    Pmpv_node_list = ^mpv_node_list;

    mpv_node_list = packed record
        num : int64;
        values : Pmpv_node;
        keys : ^Pchar;
      end;

    _u = packed record
        case integer of
         0:( string_ : Pchar);
         1:( flag_   : longint);
         2:( double_ : double);
         3:( list_   : Pmpv_node_list);
         4:( int64_  : int64);
       end;


    mpv_node = packed record
        u: _u;
        format : mpv_format;
      end;
  {*
   * (see mpv_node)
    }
  {*
       * Number of entries. Negative values are not allowed.
        }
  {*
       * MPV_FORMAT_NODE_ARRAY:
       *  values[N] refers to value of the Nth item
       *
       * MPV_FORMAT_NODE_MAP:
       *  values[N] refers to value of the Nth key/value pair
       *
       * If num > 0, values[0] to values[num-1] (inclusive) are valid.
       * Otherwise, this can be NULL.
        }
  {*
       * MPV_FORMAT_NODE_ARRAY:
       *  unused (typically NULL), access is not allowed
       *
       * MPV_FORMAT_NODE_MAP:
       *  keys[N] refers to key of the Nth key/value pair. If num > 0, keys[0] to
       *  keys[num-1] (inclusive) are valid. Otherwise, this can be NULL.
       *  The keys are in random order. The only guarantee is that keys[N] belongs
       *  to the value values[N]. NULL keys are not allowed.
        }

  {*
   * Frees any data referenced by the node. It doesn't free the node itself.
   * Call this only if the mpv client API set the node. If you constructed the
   * node yourself (manually), you have to free it yourself.
    }

  var
    mpv_free_node_contents : procedure(var node:mpv_node);cdecl;
  {*
   * Set an option. Note that you can't normally set options during runtime. It
   * works in uninitialized state (see mpv_create()), and in some cases in at
   * runtime.
   *
   * Changing options at runtime does not always work. For some options, attempts
   * to change them simply fails. Many other options may require reloading the
   * file for changes to take effect. In general, you should prefer calling
   * mpv_set_property() to change settings during playback, because the property
   * mechanism guarantees that changes take effect immediately.
   *
   * @param name Option name. This is the same as on the mpv command line, but
   *             without the leading "--".
   * @param format see enum mpv_format.
   * @param[in] data Option value (according to the format).
   * @return error code
    }

    mpv_set_option : function(var ctx:mpv_handle; name:Pchar; format:mpv_format; data:pointer):longint;cdecl;
  {*
   * Convenience function to set an option to a string value. This is like
   * calling mpv_set_option() with MPV_FORMAT_STRING.
   *
   * @return error code
    }


    mpv_set_option_string : function(var ctx:mpv_handle; name:Pchar; data:Pchar):longint;cdecl;
  {*
   * Send a command to the player. Commands are the same as those used in
   * input.conf, except that this function takes parameters in a pre-split
   * form.
   *
   * The commands and their parameters are documented in input.rst.
   *
   * @param[in] args NULL-terminated list of strings. Usually, the first item
   *                 is the command, and the following items are arguments.
   * @return error code
    }

    mpv_command : function(var ctx:mpv_handle; args:PPchar):longint;cdecl;
  {*
   * Same as mpv_command, but use input.conf parsing for splitting arguments.
   * This is slightly simpler, but also more error prone, since arguments may
   * need quoting/escaping.
    }

    mpv_command_string : function(var ctx:mpv_handle; args:Pchar):longint;cdecl;
  {*
   * Same as mpv_command, but run the command asynchronously.
   *
   * Commands are executed asynchronously. You will receive a
   * MPV_EVENT_COMMAND_REPLY event. (This event will also have an
   * error code set if running the command failed.)
   *
   * @param reply_userdata see section about asynchronous calls
   * @param args NULL-terminated list of strings (see mpv_command())
   * @return error code
    }

    mpv_command_async : function(var ctx:mpv_handle; reply_userdata:cuint64; args:PPchar):longint;cdecl;
  {*
   * Set a property to a given value. Properties are essentially variables which
   * can be queried or set at runtime. For example, writing to the pause property
   * will actually pause or unpause playback.
   *
   * If the format doesn't match with the internal format of the property, access
   * usually will fail with MPV_ERROR_PROPERTY_FORMAT. In some cases, the data
   * is automatically converted and access succeeds. For example, MPV_FORMAT_INT64
   * is always converted to MPV_FORMAT_DOUBLE, and access using MPV_FORMAT_STRING
   * usually invokes a string parser.
   *
   * @param name The property name. See input.rst for a list of properties.
   * @param format see enum mpv_format.
   * @param[in] data Option value.
   * @return error code
    }

    mpv_set_property : function(var ctx:mpv_handle; name:Pchar; format:mpv_format; data:pointer):longint;cdecl;
  {*
   * Convenience function to set a property to a string value.
   *
   * This is like calling mpv_set_property() with MPV_FORMAT_STRING.
    }


    mpv_set_property_string : function(var ctx:mpv_handle; name:Pchar; data:Pchar):longint;cdecl;
  {*
   * Set a property asynchronously. You will receive the result of the operation
   * as MPV_EVENT_SET_PROPERTY_REPLY event. The mpv_event.error field will contain
   * the result status of the operation. Otherwise, this function is similar to
   * mpv_set_property().
   *
   * @param reply_userdata see section about asynchronous calls
   * @param name The property name.
   * @param format see enum mpv_format.
   * @param[in] data Option value. The value will be copied by the function. It
   *                 will never be modified by the client API.
   * @return error code if sending the request failed
    }

    mpv_set_property_async : function(var ctx:mpv_handle; reply_userdata:cuint64; name:Pchar; format:mpv_format; var data:pointer):longint;cdecl;
  {*
   * Read the value of the given property.
   *
   * If the format doesn't match with the internal format of the property, access
   * usually will fail with MPV_ERROR_PROPERTY_FORMAT. In some cases, the data
   * is automatically converted and access succeeds. For example, MPV_FORMAT_INT64
   * is always converted to MPV_FORMAT_DOUBLE, and access using MPV_FORMAT_STRING
   * usually invokes a string formatter.
   *
   * @param name The property name.
   * @param format see enum mpv_format.
   * @param[out] data Pointer to the variable holding the option value. On
   *                  success, the variable will be set to a copy of the option
   *                  value. For formats that require dynamic memory allocation,
   *                  you can free the value with mpv_free() (strings) or
   *                  mpv_free_node_contents() (MPV_FORMAT_NODE).
   * @return error code
    }

    mpv_get_property : function(var ctx:mpv_handle; name:Pchar; format:mpv_format; data:pointer):longint;cdecl;
  {*
   * Return the value of the property with the given name as string. This is
   * equivalent to mpv_get_property() with MPV_FORMAT_STRING.
   *
   * See MPV_FORMAT_STRING for character encoding issues.
   *
   * On error, NULL is returned. Use mpv_get_property() if you want fine-grained
   * error reporting.
   *
   * @param name The property name.
   * @return Property value, or NULL if the property can't be retrieved. Free
   *         the string with mpv_free().
    }

    mpv_get_property_string : function(var ctx:mpv_handle; name:Pchar):Pchar;cdecl;
  {*
   * Return the property as "OSD" formatted string. This is the same as
   * mpv_get_property_string, but using MPV_FORMAT_OSD_STRING.
   *
   * @return Property value, or NULL if the property can't be retrieved. Free
   *         the string with mpv_free().
    }

    mpv_get_property_osd_string : function(var ctx:mpv_handle; name:Pchar):Pchar;cdecl;
  {*
   * Get a property asynchronously. You will receive the result of the operation
   * as well as the property data with the MPV_EVENT_GET_PROPERTY_REPLY event.
   * You should check the mpv_event.error field on the reply event.
   *
   * @param reply_userdata see section about asynchronous calls
   * @param name The property name.
   * @param format see enum mpv_format.
   * @return error code if sending the request failed
    }

    mpv_get_property_async : function(var ctx:mpv_handle; reply_userdata:cuint64; name:Pchar; format:mpv_format):longint;cdecl;
  {*
   * Get a notification whenever the given property changes. You will receive
   * updates as MPV_EVENT_PROPERTY_CHANGE. Note that this is not very precise:
   * it can send updates even if the property in fact did not change, or (in
   * some cases) not send updates even if the property changed - it usually
   * depends on the property. It's a valid feature request to ask for better
   * update handling of a specific property.
   *
   * Property changes are coalesced: the change events are returned only once the
   * event queue becomes empty (e.g. mpv_wait_event() would block or return
   * MPV_EVENT_NONE), and then only one event per changed property is returned.
   *
   * If the format parameter is set to something other than MPV_FORMAT_NONE, the
   * current property value will be returned as part of mpv_event_property. In
   * this case, the API will also suppress redundant change events by comparing
   * the raw value against the previous value.
   *
   * Warning: if a property is unavailable or retrieving it caused an error,
   *          MPV_FORMAT_NONE will be set in mpv_event_property, even if the
   *          format parameter was set to a different value. In this case, the
   *          mpv_event_property.data field is invalid.
   *
   * Observing a property that doesn't exist is allowed, although it may still
   * cause some sporadic change events.
   *
   * Keep in mind that you will get change notifications even if you change a
   * property yourself. Try to avoid endless feedback loops, which could happen
   * if you react to change notifications which you caused yourself.
   *
   * @param reply_userdata This will be used for the mpv_event.reply_userdata
   *                       field for the received MPV_EVENT_PROPERTY_CHANGE
   *                       events. (Also see section about asynchronous calls,
   *                       although this function is somewhat different from
   *                       actual asynchronous calls.)
   *                       Also see mpv_unobserve_property().
   * @param name The property name.
   * @param format see enum mpv_format. Can be MPV_FORMAT_NONE to omit values
   *               from the change events.
   * @return error code (usually fails only on OOM or unsupported format)
    }

    mpv_observe_property : function(var mpv:mpv_handle; reply_userdata:cuint64; name:Pchar; format:mpv_format):longint;cdecl;
  {*
   * Undo mpv_observe_property(). This will remove all observed properties for
   * which the given number was passed as reply_userdata to mpv_observe_property.
   *
   * @param registered_reply_userdata ID that was passed to mpv_observe_property
   * @return negative value is an error code, >=0 is number of removed properties
   *         on success (includes the case when 0 were removed)
    }
    mpv_unobserve_property : function(var mpv:mpv_handle; registered_reply_userdata:cuint64):longint;cdecl;
  {*
       * Nothing happened. Happens on timeouts or sporadic wakeups.
        }
  {*
       * Happens when the player quits. The player enters a state where it tries
       * to disconnect all clients. Most requests to the player will fail, and
       * mpv_wait_event() will always return instantly (returning new shutdown
       * events if no other events are queued). The client should react to this
       * and quit with mpv_detach_destroy() as soon as possible.
        }
  {*
       * See mpv_request_log_messages().
        }
  {*
       * Reply to a mpv_get_property_async() request.
       * See also mpv_event and mpv_event_property.
        }
  {*
       * Reply to a mpv_set_property_async() request.
       * (Unlike MPV_EVENT_GET_PROPERTY, mpv_event_property is not used.)
        }
  {*
       * Reply to a mpv_command_async() request.
        }
  {*
       * Notification before playback start of a file (before the file is loaded).
        }
  {*
       * Notification after playback end (after the file was unloaded).
       * See also mpv_event and mpv_event_end_file.
        }
  {*
       * Notification when the file has been loaded (headers were read etc.), and
       * decoding starts.
        }
  {*
       * The list of video/audio/subtitle tracks was changed. (E.g. a new track
       * was found. This doesn't necessarily indicate a track switch; for this,
       * MPV_EVENT_TRACK_SWITCHED is used.)
        }
  {*
       * A video/audio/subtitle track was switched on or off.
        }
  {*
       * Idle mode was entered. In this mode, no file is played, and the playback
       * core waits for new commands. (The command line player normally quits
       * instead of entering idle mode, unless --idle was specified. If mpv
       * was started with mpv_create(), idle mode is enabled by default.)
        }
  {*
       * Playback was paused. This indicates the logical pause state (like the
       * property "pause" as opposed to the "core-idle" propetty). This event
       * is sent whenever any pause state changes, not only the logical state,
       * so you might get multiple MPV_EVENT_PAUSE events in a row.
        }
  {*
       * Playback was unpaused. See MPV_EVENT_PAUSE for not so obvious details.
        }
  {*
       * Sent every time after a video frame is displayed (or in lower frequency
       * if there is no video, or playback is paused).
        }
  {*
       * Triggered by the script_dispatch input command. The command uses the
       * client name (see mpv_client_name()) to dispatch keyboard or mouse input
       * to a client.
       * (This is pretty obscure and largely replaced by MPV_EVENT_CLIENT_MESSAGE,
       * but still the only way to distinguish key down/up events when binding
       * script_dispatch via input.conf.)
        }
  {*
       * Triggered by the script_message input command. The command uses the
       * first argument of the command as client name (see mpv_client_name()) to
       * dispatch the message, and passes along the all arguments starting from
       * the seconand argument as strings.
       * See also mpv_event and mpv_event_client_message.
        }
  {*
       * Happens after video changed in some way. This can happen on resolution
       * changes, pixel format changes, or video filter changes. The event is
       * sent after the video filters and the VO are reconfigured. Applications
       * embedding a mpv window should listen to this event in order to resize
       * the window if needed.
       * Note that this event can happen sporadically, and you should check
       * yourself whether the video parameters really changed before doing
       * something expensive.
        }
  {*
       * Similar to MPV_EVENT_VIDEO_RECONFIG. This is relatively uninteresting,
       * because there is no such thing as audio output embedding.
        }
  {*
       * Happens when metadata (like file tags) is possibly updated. (It's left
       * unspecified whether this happens on file start or only when it changes
       * within a file.)
        }
  {*
       * Happens when a seek was initiated. Playback stops. Usually it will
       * resume with MPV_EVENT_PLAYBACK_RESTART as soon as the seek is finished.
        }
  {*
       * There was a discontinuity of some sort (like a seek), and playback
       * was reinitialized. Usually happens after seeking, or ordered chapter
       * segment switches. The main purpose is allowing the client to detect
       * when a seek request is finished.
        }
  {*
       * Event sent due to mpv_observe_property().
       * See also mpv_event and mpv_event_property.
        }
  {*
       * Happens when the current chapter changes.
        }

  type
    Pmpv_event_id = ^mpv_event_id;
    mpv_event_id =  Longint;
    Const
      MPV_EVENT_NONE = 0;
      MPV_EVENT_SHUTDOWN = 1;
      MPV_EVENT_LOG_MESSAGE = 2;
      MPV_EVENT_GET_PROPERTY_REPLY = 3;
      MPV_EVENT_SET_PROPERTY_REPLY = 4;
      MPV_EVENT_COMMAND_REPLY = 5;
      MPV_EVENT_START_FILE = 6;
      MPV_EVENT_END_FILE = 7;
      MPV_EVENT_FILE_LOADED = 8;
      MPV_EVENT_TRACKS_CHANGED = 9;
      MPV_EVENT_TRACK_SWITCHED = 10;
      MPV_EVENT_IDLE = 11;
      MPV_EVENT_PAUSE = 12;
      MPV_EVENT_UNPAUSE = 13;
      MPV_EVENT_TICK = 14;
      MPV_EVENT_SCRIPT_INPUT_DISPATCH = 15;
      MPV_EVENT_CLIENT_MESSAGE = 16;
      MPV_EVENT_VIDEO_RECONFIG = 17;
      MPV_EVENT_AUDIO_RECONFIG = 18;
      MPV_EVENT_METADATA_UPDATE = 19;
      MPV_EVENT_SEEK = 20;
      MPV_EVENT_PLAYBACK_RESTART = 21;
      MPV_EVENT_PROPERTY_CHANGE = 22;
      MPV_EVENT_CHAPTER_CHANGE = 23;

  {*
   * Return a string describing the event. For unknown events, NULL is returned.
   *
   * Note that all events actually returned by the API will also yield a non-NULL
   * string with this function.
   *
   * @param event event ID, see see enum mpv_event_id
   * @return A static string giving a short symbolic name of the event. It
   *         consists of lower-case alphanumeric characters and can include "-"
   *         characters. This string is suitable for use in e.g. scripting
   *         interfaces.
   *         The string is completely static, i.e. doesn't need to be deallocated,
   *         and is valid forever.
    }


  var
    mpv_event_name : function(event:mpv_event_id):Pchar;cdecl;
  {*
       * Name of the property.
        }

  {*
       * Format of the given data. See enum mpv_format.
       * This is always the same format as the requested format.
        }
  {*
       * Received property value. Depends on the format. This is like the
       * pointer argument passed to mpv_get_property().
       *
       * For example, for MPV_FORMAT_STRING you get the string with:
       *
       *    char *value = *(char **)(event_property->data);
       *
       * Note that this is set to NULL if retrieving the property failed.
       * See mpv_event.error for the status.
        }

  type
    Pmpv_event_property = ^mpv_event_property;
    mpv_event_property = packed record
        name : Pchar;
        format : mpv_format;
        data : pointer;
      end;
  {*
       * The module prefix, identifies the sender of the message.
        }

  {*
       * The log level as string. See mpv_request_log_messages() for possible
       * values.
        }

  {*
       * The log message. Note that this is the direct output of a printf()
       * style output API. The text will contain embedded newlines, and it's
       * possible that a single message contains multiple lines, or that a
       * message contains a partial line.
       *
       * It's safe to display messages only if they end with a newline character,
       * and to buffer them otherwise.
        }


    Pmpv_event_log_message = ^_mpv_event_log_message;
    _mpv_event_log_message = packed record
        prefix : Pchar;
        level : Pchar;
        text : Pchar;
      end;
  {*
       * Identifies the reason why playback was stopped:
       *  0: the end of the file was reached or initialization failed
       *  1: the file is restarted (e.g. edition switching)
       *  2: playback was aborted by an external action (e.g. playlist controls)
       *  3: the player received the quit command
       * Other values should be treated as unknown.
        }

    Pmpv_event_end_file = ^_mpv_event_end_file;
    _mpv_event_end_file = packed record
        reason : longint;
      end;
  {*
       * Arbitrary integer value that was provided as argument to the
       * script_dispatch input command.
        }
  {*
       * Type of the input. Currently either "keyup_follows" (basically a key
       * down event), or "press" (either a single key event, or a key up event
       * following a "keyup_follows" event).
        }


    Pmpv_event_script_input_dispatch = ^_mpv_event_script_input_dispatch;
    _mpv_event_script_input_dispatch = packed record
        arg0 : longint;
        _type : Pchar;
      end;
  {*
       * Arbitrary arguments chosen by the sender of the message. If num_args > 0,
       * you can access args[0] through args[num_args - 1] (inclusive). What
       * these arguments mean is up to the sender and receiver.
       * None of the valid items are NULL.
        }


    Pmpv_event_client_message = ^_mpv_event_client_message;
    _mpv_event_client_message = packed record
        num_args : longint;
        args : ^Pchar;
      end;
  {*
       * One of mpv_event. Keep in mind that later ABI compatible releases might
       * add new event types. These should be ignored by the API user.
        }
  {*
       * This is mainly used for events that are replies to (asynchronous)
       * requests. It contains a status code, which is >= 0 on success, or < 0
       * on error (a mpv_error value). Usually, this will be set if an
       * asynchronous request fails.
        }
  {*
       * If the event is in reply to a request (made with this API and this
       * API handle), this is set to the reply_userdata parameter of the request
       * call.
       * Otherwise, this field is 0.
        }
  {*
       * The meaning and contents of the data member depend on the event_id:
       *  MPV_EVENT_GET_PROPERTY_REPLY:     mpv_event_property*
       *  MPV_EVENT_PROPERTY_CHANGE:        mpv_event_property*
       *  MPV_EVENT_LOG_MESSAGE:            mpv_event_log_message*
       *  MPV_EVENT_SCRIPT_INPUT_DISPATCH:  mpv_event_script_input_dispatch*
       *  MPV_EVENT_CLIENT_MESSAGE:         mpv_event_client_message*
       *  MPV_EVENT_END_FILE:               mpv_event_end_file*
       *  other: NULL
       *
       * Note: future enhancements might add new event structs for existing or new
       *       event types.
        }

    Pmpv_event = ^mpv_event;
    mpv_event = packed record
        event_id : mpv_event_id;
        error : longint;
        reply_userdata : cuint64;
        data : pointer;
      end;

    mpv_callback = procedure (d:pointer); cdecl;

  {*
   * Enable or disable the given event.
   *
   * Some events are enabled by default. Some events can't be disabled.
   *
   * (Informational note: currently, all events are enabled by default, except
   *  MPV_EVENT_TICK.)
   *
   * @param event See enum mpv_event_id.
   * @param enable 1 to enable receiving this event, 0 to disable it.
   * @return error code
    }

  var
    mpv_request_event : function(var ctx:mpv_handle; event:mpv_event_id; enable:longint):longint;cdecl;
  {*
   * Enable or disable receiving of log messages. These are the messages the
   * command line player prints to the terminal. This call sets the minimum
   * required log level for a message to be received with MPV_EVENT_LOG_MESSAGE.
   *
   * @param min_level Minimal log level as string. Valid log levels:
   *                      no fatal error warn info status v debug trace
   *                  The value "no" disables all messages. This is the default.
    }

    mpv_request_log_messages : function(var ctx:mpv_handle; min_level:Pchar):longint;cdecl;
  {*
   * Wait for the next event, or until the timeout expires, or if another thread
   * makes a call to mpv_wakeup(). Passing 0 as timeout will never wait, and
   * is suitable for polling.
   *
   * The internal event queue has a limited size (per client handle). If you
   * don't empty the event queue quickly enough with mpv_wait_event(), it will
   * overflow and silently discard further events. If this happens, making
   * asynchronous requests will fail as well (with MPV_ERROR_EVENT_QUEUE_FULL).
   *
   * Only one thread is allowed to call this at a time. The API won't complain
   * if more than one thread calls this, but it will cause race conditions in
   * the client when accessing the shared mpv_event struct. Note that most other
   * API functions are not restricted by this, and no API function internally
   * calls mpv_wait_event().
   *
   * @param timeout Timeout in seconds, after which the function returns even if
   *                no event was received. A MPV_EVENT_NONE is returned on
   *                timeout. A value of 0 will disable waiting. Negative values
   *                will wait with an infinite timeout.
   * @return A struct containing the event ID and other data. The pointer (and
   *         fields in the struct) stay valid until the next mpv_wait_event()
   *         call, or until the mpv_handle is destroyed. You must not write to
   *         the struct, and all memory referenced by it will be automatically
   *         released by the API. The return value is never NULL.
    }
    mpv_wait_event : function(var ctx:mpv_handle; timeout:double):Pmpv_event;cdecl;
  {*
   * Interrupt the current mpv_wait_event() call. This will wake up the thread
   * currently waiting in mpv_wait_event(). If no thread is waiting, the next
   * mpv_wait_event() call will return immediately (this is to avoid lost
   * wakeups).
   *
   * mpv_wait_event() will receive a MPV_EVENT_NONE if it's woken up due to
   * this call. But note that this dummy event might be skipped if there are
   * already other events queued. All what counts is that the waiting thread
   * is woken up at all.
    }
    mpv_wakeup : procedure(var ctx:mpv_handle);cdecl;
  {*
   * Set a custom function that should be called when there are new events. Use
   * this if blocking in mpv_wait_event() to wait for new events is not feasible.
   *
   * Keep in mind that the callback will be called from foreign threads. You
   * must not make any assumptions of the environment, and you must return as
   * soon as possible. You are not allowed to call any client API functions
   * inside of the callback. In particular, you should not do any processing in
   * the callback, but wake up another thread that does all the work. It's also
   * possible that the callback is called from a thread while a mpv API function
   * is called (i.e. it can be reentrant).
   *
   * In general, the client API expects you to call mpv_wait_event() to receive
   * notifications, and the wakeup callback is merely a helper utility to make
   * this easier in certain situations. Note that it's possible that there's
   * only one wakeup callback invocation for multiple events. You should call
   * mpv_wait_event() with no timeout until MPV_EVENT_NONE is reached, at which
   * point the event queue is empty.
   *
   * If you actually want to do processing in a callback, spawn a thread that
   * does nothing but call mpv_wait_event() in a loop and dispatches the result
   * to a callback.
   *
   * Only one wakeup callback can be set.
   *
   * @param cb function that should be called if a wakeup is required
   * @param d arbitrary userdata passed to cb
    }

    mpv_set_wakeup_callback : procedure(var ctx:mpv_handle; cb:mpv_callback; d:pointer);cdecl;
  {*
   * Return a UNIX file descriptor referring to the read end of a pipe. This
   * pipe can be used to wake up a poll() based processing loop. The purpose of
   * this function is very similar to mpv_set_wakeup_callback(), and provides
   * a primitive mechanism to handle coordinating a foreign event loop and the
   * libmpv event loop. The pipe is non-blocking. It's closed when the mpv_handle
   * is destroyed. This function always returns the same value (on success).
   *
   * This is in fact implemented using the same underlying code as for
   * mpv_set_wakeup_callback() (though they don't conflict), and it is as if each
   * callback invocation writes a single 0 byte to the pipe. When the pipe
   * becomes readable, the code calling poll() (or select()) on the pipe should
   * read all contents of the pipe and then call mpv_wait_event(c, 0) until
   * no new events are returned. The pipe contents do not matter and can just
   * be discarded. There is not necessarily one byte per readable event in the
   * pipe. For example, the pipes are non-blocking, and mpv won't block if the
   * pipe is full. Pipes are normally limited to 4096 bytes, so if there are
   * more than 4096 events, the number of readable bytes can not equal the number
   * of events queued. Also, it's possible that mpv does not write to the pipe
   * once it's guaranteed that the client was already signaled. See the example
   * below how to do it correctly.
   *
   * Example:
   *
   *  int pipefd = mpv_get_wakeup_pipe(mpv);
   *  if (pipefd < 0)
   *      error();
   *  while (1)
   *      struct pollfd pfds[1] =
   *           .fd = pipefd, .events = POLLIN ,
   *      ;
   *      // Wait until there are possibly new mpv events.
   *      poll(pfds, 1, -1);
   *      if (pfds[0].revents & POLLIN)
   *          // Empty the pipe. Doing this before calling mpv_wait_event()
   *          // ensures that no wakeups are missed. It's not so important to
   *          // make sure the pipe is really empty (it will just cause some
   *          // additional wakeups in unlikely corner cases).
   *          char unused[256];
   *          read(pipefd, unused, sizeof(unused));
   *          while (1)
   *              mpv_event *ev = mpv_wait_event(mpv, 0);
   *              // If MPV_EVENT_NONE is received, the event queue is empty.
   *              if (ev->event_id == MPV_EVENT_NONE)
   *                  break;
   *              // Process the event.
   *              ...
   *
   *
   *
   *
   * @return A UNIX FD of the read end of the wakeup pipe, or -1 on error.
   *         On MS Windows/MinGW, this will always return -1.
    }
    mpv_get_wakeup_pipe : function(var ctx:mpv_handle):longint;cdecl;


Function Check_libmpv:boolean;
procedure Load_libmpv(lib : pchar);
procedure Free_libmpv;

implementation

  uses
    SysUtils, dynlibs;

  var
    hlib : tlibhandle;


  procedure Free_libmpv;
    begin
      FreeLibrary(hlib);
      mpv_client_api_version:=nil;
      mpv_error_string:=nil;
      mpv_free:=nil;
      mpv_client_name:=nil;
      mpv_create:=nil;
      mpv_initialize:=nil;
      mpv_detach_destroy:=nil;
      mpv_terminate_destroy:=nil;
      mpv_load_config_file:=nil;
      mpv_suspend:=nil;
      mpv_resume:=nil;
      mpv_get_time_us:=nil;
      mpv_free_node_contents:=nil;
      mpv_set_option:=nil;
      mpv_set_option_string:=nil;
      mpv_command:=nil;
      mpv_command_string:=nil;
      mpv_command_async:=nil;
      mpv_set_property:=nil;
      mpv_set_property_string:=nil;
      mpv_set_property_async:=nil;
      mpv_get_property:=nil;
      mpv_get_property_string:=nil;
      mpv_get_property_osd_string:=nil;
      mpv_get_property_async:=nil;
      mpv_observe_property:=nil;
      mpv_unobserve_property:=nil;
      mpv_event_name:=nil;
      mpv_request_event:=nil;
      mpv_request_log_messages:=nil;
      mpv_wait_event:=nil;
      mpv_wakeup:=nil;
      mpv_set_wakeup_callback:=nil;
      mpv_get_wakeup_pipe:=nil;
    end;


  procedure Load_libmpv(lib : pchar);
    begin
      hlib:=LoadLibrary(lib);
      if hlib=0 then
        Exit;

      pointer(mpv_client_api_version):=GetProcAddress(hlib,'mpv_client_api_version');
      pointer(mpv_error_string):=GetProcAddress(hlib,'mpv_error_string');
      pointer(mpv_free):=GetProcAddress(hlib,'mpv_free');
      pointer(mpv_client_name):=GetProcAddress(hlib,'mpv_client_name');
      pointer(mpv_create):=GetProcAddress(hlib,'mpv_create');
      pointer(mpv_initialize):=GetProcAddress(hlib,'mpv_initialize');
      pointer(mpv_detach_destroy):=GetProcAddress(hlib,'mpv_detach_destroy');
      pointer(mpv_terminate_destroy):=GetProcAddress(hlib,'mpv_terminate_destroy');
      pointer(mpv_load_config_file):=GetProcAddress(hlib,'mpv_load_config_file');
      pointer(mpv_suspend):=GetProcAddress(hlib,'mpv_suspend');
      pointer(mpv_resume):=GetProcAddress(hlib,'mpv_resume');
      pointer(mpv_get_time_us):=GetProcAddress(hlib,'mpv_get_time_us');
      pointer(mpv_free_node_contents):=GetProcAddress(hlib,'mpv_free_node_contents');
      pointer(mpv_set_option):=GetProcAddress(hlib,'mpv_set_option');
      pointer(mpv_set_option_string):=GetProcAddress(hlib,'mpv_set_option_string');
      pointer(mpv_command):=GetProcAddress(hlib,'mpv_command');
      pointer(mpv_command_string):=GetProcAddress(hlib,'mpv_command_string');
      pointer(mpv_command_async):=GetProcAddress(hlib,'mpv_command_async');
      pointer(mpv_set_property):=GetProcAddress(hlib,'mpv_set_property');
      pointer(mpv_set_property_string):=GetProcAddress(hlib,'mpv_set_property_string');
      pointer(mpv_set_property_async):=GetProcAddress(hlib,'mpv_set_property_async');
      pointer(mpv_get_property):=GetProcAddress(hlib,'mpv_get_property');
      pointer(mpv_get_property_string):=GetProcAddress(hlib,'mpv_get_property_string');
      pointer(mpv_get_property_osd_string):=GetProcAddress(hlib,'mpv_get_property_osd_string');
      pointer(mpv_get_property_async):=GetProcAddress(hlib,'mpv_get_property_async');
      pointer(mpv_observe_property):=GetProcAddress(hlib,'mpv_observe_property');
      pointer(mpv_unobserve_property):=GetProcAddress(hlib,'mpv_unobserve_property');
      pointer(mpv_event_name):=GetProcAddress(hlib,'mpv_event_name');
      pointer(mpv_request_event):=GetProcAddress(hlib,'mpv_request_event');
      pointer(mpv_request_log_messages):=GetProcAddress(hlib,'mpv_request_log_messages');
      pointer(mpv_wait_event):=GetProcAddress(hlib,'mpv_wait_event');
      pointer(mpv_wakeup):=GetProcAddress(hlib,'mpv_wakeup');
      pointer(mpv_set_wakeup_callback):=GetProcAddress(hlib,'mpv_set_wakeup_callback');
      pointer(mpv_get_wakeup_pipe):=GetProcAddress(hlib,'mpv_get_wakeup_pipe');
    end;

  Function Check_libmpv:boolean;
  var
    cdir: string;
    MustFree :boolean ;
  begin
    // no error
    MustFree := hlib = 0;

    Load_libmpv(External_library);
    Result:=false;
    // exit, report error
    if (hlib = 0) then
      begin
      end
    else
      begin
        Result:=true;
        if MustFree then
           begin
             UnloadLibrary(hlib);
             hlib := 0;
           end;
      end;
  end;

initialization
    hlib := 0;
finalization

end.

